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PART 1. 



STRUCTURE OF VESSELS. 



Vessels are constructed of wood under two 

 forms, Plank and Timbers ; Plank, the out and in- 

 side skin of the vessel — Timbers, the ribs or frame . 

 which support the plank. 



SECTION I. PLANK. 



Trees intended for plank ought to be reared in 

 close forest, or protected situation, drawn tall and 

 straight, or what is preferable for a part, with a 

 gentle regular bend, technically sny, Figs, v and x, 

 (next page). It requires to be^of clean solid texture, 

 from 121 to 40 feet in length, and at least 8 inches 

 in. diameter at small end, or any greater thickness. 

 For the conveniency of transport, oak plank timber 

 is generally squared or planked where grown, and is 

 cut out from 2 J to 7 inches in thickness, and from 

 6 to 18 inches in breadth. Plank is needed of such 

 various dimensions, that any oak tree of clean tim- 

 ber, nearly straight one way, and straight, or with 

 a gentle regular bending, the other, may safely be 

 cut into plank, the section to be in the plane of the 



